Bug 108906 – 'dictionary' should be supported by WebKit IDL

• Status: RESOLVED
• Resolution: CONFIGURATION CHANGED
• Component: WebCore JavaScript

[Kentaro Hara]

Web IDL spec: http://www.w3.org/TR/WebIDL/#idl-dictionaries

Use cases: https://cvs.khronos.org/svn/repos/registry/trunk/public/webcl/spec/latest/index.html

Currently 'dictionary' is parsed by IDLParser.pm but it is ignored by code generators.

[Kentaro Hara]

FYI, there had been a plan to use 'dictionary' for event constructors. There should be other use cases in the future.

[Antonio Gomes]

Kentaro told me, @nbarth won't be able to work on this for now. Taking ...

[Alexey Proskuryakov]

WebCrypto uses dictionaries too.

That said, it seems unclear how "dictionary" is different from "interface", except for minor syntactic sugar. Can someone please explain?

[Alexey Proskuryakov]

Or rather how it's different from Object, I guess.

[Antonio Gomes]

(In reply to comment #3)
> WebCrypto uses dictionaries too.
> 
> That said, it seems unclear how "dictionary" is different from "interface", except for minor syntactic sugar. Can someone please explain?

That is a good question. I would say a 'dictionary' is the as a strong-typed 'interface with only read-only parameters'.

For example:

- in JS: var a = {x: bleh, y: blah};
- in c++:
the dictionary would have "x" member variable defined whose type is a Bleh class. IDL would have something like:

dictionary Foo {
Bleh x;
Blah y;
}

Based on the, the the binding could do the casts needed.

Please correct if I am wrong. It lacks a formal definition in WebIDL as far as I can tell.

[Anne van Kesteren]

Looking at how this works for addEventListener() this appears to be resolved.